#include <stdio.h>



int main()

{

    int a, b, c = 0;

    while (scanf("%d %d %d", &a, &b, &c) != EOF)

    {

        if (a + c > b && a + b > c && b + c > a)

            if (a == b && b == c)

                printf("Equilateral triangle!\n");

            else if (a == b || b == c || a == c)

                printf("Isosceles triangle!\n");

            else

                printf("Ordinary triangle!\n");

        else

            printf("Not a triangle!\n");

    }

    return 0;

}